My favorite is RuneScape’s style of payment. I personally feel it is the best payment method. There’s F2P and P2P worlds. Free to Play has access to 20 or so quests, a quarter of the map, and access to about half of the skills. When you pay the $8 monthly fee for membership you unlock every skill, faster training methods, the whole map, and every quest. I believe it’s the best because it allows players to play the game for free, they get hooked, complete all the F2P stuff, and buy membership. Since membership is such a low fee players are willing to pay it and it allows them to go several months without getting bored. Plus if you buy more than one month you get a few dollars off so often times players will buy a full year of subscription and if they get bored and quit before the year is up Jagex still has the money.
My only problem with RuneScape now is that in recent years a company bought 50% of Jagex so now things like Solomon’s Store (a cosmetic item shop), and Treasure Hunter (Basically like gambling, spend money on keys, unlock the chest and you can get xp, untradeable powerful weapons, etc).